Development of an image reconstruction method for quantitative profiling of -ray sources at close range using Si/CdTe Compton camera

Nagao, Yuto; Yamaguchi, Mitsutaka; Kawachi, Naoki; Fujimaki, Shu; Kamiya, Tomihiro; Takeda, Shinichiro*; Odaka, Hirokazu*; Watanabe, Shin*; Kokubun, Motohide*; Takahashi, Tadayuki*; Torikai, Kota*; Shimada, Hirofumi*; Arakawa, Kazuo*; Suzuki, Yoshiyuki*; Nakano, Takashi*

A conventional -ray imaging system such as a gamma camera and SPECT has a fundamental problem that imposes a tradeoff between sensitivity and spatial resolution and restricts -ray energy to low because of the physical constraints resulting from the mechanical collimation. On the other hand, a Compton camera, which applies kinematics of Compton scattering to the electronic collimation, is a next generation -ray imaging system which decouples the tradeoff between sensitivity and spatial resolution and covers a wide range of energy. We study an application of a Si/CdTe semiconductor Compton camera being developed for space observation to in vivo tracer imaging in medicine and biology. Particularly, it is essential for a medical and biological application to estimate quantitative distribution of tracers in a field close to the camera. We developed an image reconstruction method to realize quantitative profiling of -ray emitting sources.